This invention relates to a process for coating a disposed silicone gel or grease.
It is known to dispose a tacky silicone gel or grease (also called a compound) on an electrical device, such as on a crimp-on electrical connector for the purposes of coating and protecting an electrical junction that is established or maintained during the use of the connector or on an electrical circuit board to protect components and connections thereon against damage by corrosion, vibration, mechanical shock and the like. The sticky nature of the tacky silicone gel or grease is used to establish adhesion between the silicone material and the substrate on which it is placed. The gel- or grease-like nature of the tacky silicone is used to permit deformation and limited flow of the silicone material under stress, such as during its application to the substrate, during use of a treated electrical connector or during invasive testing or repair of a coated circuit board, and yet prevent flow of the disposed gel or grease away from the substrate.
However, the exposed surface of the disposed tacky silicone grease or gel, in many cases, need not be sticky and therefore unnecessarily presents problems. For example, unless covered, the sticky surface will collect dirt, the presence of which is usually undesirable for operational and/or aesthetic reasons. Additionally, a small substrate which bears exposed gel or grease will tend to stick in undesirable locations unless it is specially packaged and/or handled. In particular, a plurality of grease- or gel-containing electrical connectors tend to aggregate when handled in bulk form in the absence of further precautions.
It is further known to coat a disposed tacky silicone gel or grease with a moisture- or heat-curable, liquid organopolysiloxane composition and thereafter allow the coating to cure to a solid non-tacky state, thereby providing a solution to the sticky problems noted above. However, said curable, liquid organopolysiloxane compositions have one or more deficiences, such as a slow cure rate or the presence of a solvent or the need for heat to effect a cure, that makes their use less-than-optimum.